Virus-like particles (VLPs) closely resemble mature virions, but they do not contain viral genomic material (e.g., viral genomic RNA). Therefore, VLPs are nonreplicative in nature, which make them safe for administration in the form of an immunogenic composition (e.g., vaccine). In addition, VLPs can express envelope glycoproteins on the surface of the VLP, which is the most physiological configuration. Moreover, since VLPs resemble intact virions and are multivalent particulate structures, VLPs may be more effective in inducing neutralizing antibodies to the envelope glycoprotein than soluble envelope antigens. Further, VLPs can be administered repeatedly to vaccinated hosts, unlike many recombinant vaccine approaches. An example of a VLP vaccine is the baculovirus-derived recombinant human papillomavirus type (HPV-16) L1 VLP, which was manufactured by Novavax, Inc.
Therefore, VLPs can be used to overcome problems encountered in previous attempts to create vaccines for various viruses such as human immunodeficiency virus (HIV), Ebola virus, severe acute respiratory syndrome (SARS), coronavirus, and Rift Valley Fever virus (RVFV).